[PATCH 5.3 186/197] btrfs: tracepoints: Fix wrong parameter order for qgroup events

From: Greg Kroah-Hartman
Date: Sun Oct 27 2019 - 17:26:45 EST


From: Qu Wenruo <wqu@xxxxxxxx>

commit fd2b007eaec898564e269d1f478a2da0380ecf51 upstream.

[BUG]
For btrfs:qgroup_meta_reserve event, the trace event can output garbage:

qgroup_meta_reserve: 9c7f6acc-b342-4037-bc47-7f6e4d2232d7: refroot=5(FS_TREE) type=DATA diff=2

The diff should always be alinged to sector size (4k), so there is
definitely something wrong.

[CAUSE]
For the wrong @diff, it's caused by wrong parameter order.
The correct parameters are:

struct btrfs_root, s64 diff, int type.

However the parameters used are:

struct btrfs_root, int type, s64 diff.

Fixes: 4ee0d8832c2e ("btrfs: qgroup: Update trace events for metadata reservation")
CC: stable@xxxxxxxxxxxxxxx # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/btrfs/qgroup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -3617,7 +3617,7 @@ int __btrfs_qgroup_reserve_meta(struct b
return 0;

BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
- trace_qgroup_meta_reserve(root, type, (s64)num_bytes);
+ trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
ret = qgroup_reserve(root, num_bytes, enforce, type);
if (ret < 0)
return ret;
@@ -3664,7 +3664,7 @@ void __btrfs_qgroup_free_meta(struct btr
*/
num_bytes = sub_root_meta_rsv(root, num_bytes, type);
BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
- trace_qgroup_meta_reserve(root, type, -(s64)num_bytes);
+ trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
num_bytes, type);
}